Sir Thomas Barlow, 1st Baronet KCVO FRS[1] FRCP (4 November 1845 – 15 January 1945) was a British royal physician, known for his research on infantile scurvy.

Plaque to Thomas Barlow at his birthplace, Brandwood Fold, Edgworth.

Barlow was the son of a Lancashire cotton manufacturer and Mayor of Bolton, James Barlow (1819–1887). The family were well known as philanthropists in their home village of Edgworth where they funded charities connected with the Methodist church including the Children's Home.He studied as an undergraduate at Manchester and London. University College London (UCL) Bachelor of Medicine (BM) in 1873 and Doctor of Medicine (MD) 1874. He became a registrar at Great Ormond Street Hospital, and later a physician and in 1899 a consultant. He was professor at the UCL from 1895 to 1907, initially of paediatrics and later of clinical medicine. Barlow's disease — infantile scurvy — is named after him.[2]

He was Royal Physician to Queen Victoria and attended her on her death, and to King Edward VII and King George V. In 1902 he was created a Baronet, of Wimpole Street in St Marylebone in the County of London. He was President of the Royal College of Physicians from 1910–1914 and delivered their Harveian Oration in 1916 on the subject of Harvey, The Man and the Physician. He was elected a Foreign Honorary Member of the American Academy of Arts and Sciences in 1918.

Barlow married Ada Helen Dalmahoy, daughter of Patrick Dalmahoy, on 28 December 1880. They had the following children: